Environmental assessment of gamma-radiation levels in stream sediments around Sharm El-Sheikh, South Sinai, Egypt

A total surface area of ∼170 km2 including 28 localities around Sharm El-Sheikh, South Sinai, were investigated by γ-ray spectroscopy. The concentrations of NORM were found to be five to seven-fold that in dune sands in different regions in Sinai. While relatively higher levels of 238U, 234Th, 226Ra, and 232Th are associated with the existing monzo-syenogranite, the concentration of 40K is more uniformly distributed in the studied area. Locations with higher concentrations of 137Cs are mainly located in the northern part. The 238U, 234Th and 226Ra isotopes in the 238U-series are in secular equilibrium. The absorbed dose rates and gamma-radiation hazard indices in all locations were higher than the world average value and unity, respectively. Properly regulated land use is recommended for a buffer zone in the northern part of the study area. - Highlights: ► Concentrations of NORM were found to be 5–7-fold that in sands in different regions in Sinai. ► Higher levels of 238U, 234Th, and 232Th are associated with the present monzo-syenogranite. ► Higher concentrations of 137Cs are located in the northern part. ► Absorbed dose rates and hazard indices in all locations were higher than the world average value and unity, respectively.